Insights & Outcomes Microbial cities, leaky membranes, and Einstein rings

Yale researchers discover key information about bacterial biofilms, gravitational lensing, and a new class of long-lived holes in the nuclear membrane of cells.

8 min read

A basal plane view of a biofilm. (Credit: J.Yan and collaborators)

A basal plane view of a biofilm.

This month, Insights & Outcomes rolls up its sleeves for some new research on plugging holes in leaky nuclear membranes, boosting the carbon storage abilities of agricultural soil, digging under the surface of microbial cities, and finding a cosmic “ring.” There are student and faculty honors to share, as well.

As always, you can find more science and medicine research news on Yale News’ Science & Technology and Health & Medicine pages.

Microbial city limits

A new study shows that bacterial biofilms — tiny, microbial cities in which bacteria cooperate and compete to build a community attached to a non-biological surface — are shaped to a large degree by the firmness of their foundations.

This short video shows a basal plane view of a biofilm. (Credit: J.Yan and collaborators)

For the study, published in the journal Nature Physics, researchers from Yale, Pennsylvania State University, and the Massachusetts Institute of Technology tested some of the boundary limits of bacterial biofilm made by Vibrio cholerae, the causal agent of the pandemic cholera. Vibrio cholerae cells have a curved-rod shape and are packed densely in a biofilm, similar to molecules in a liquid crystal display.

The researchers found that defects in the surface area prevented Vibrio cholerae cells from forming into their typically highly ordered, parallel structures. Interaction with non-biological surfaces also constrained the trajectory of cell growth.

“This paper may help us understand how organisms grow as active matter, a term used in the condensed matter physics community, and may lead to new ways to engineer cell collectives,” said Jing Yan, an assistant professor of molecular, cellular, and developmental biology in Yale’s Faculty of Arts and Sciences and co-corresponding author of the study.

In addition to Yan, Yale authors of the study included co-first author Japinder Nijjer, Qiuting Zhang, and Jung-Shen B. Tai.

yAISES earns national chapter award

The Yale chapter of the American Indian Science and Engineering Society (yAISES) brought home national honors from the three-day AISES national conference in Spokane, Washington, in October.

yAISES members who attended the conference posing with the award onstage at the 2023 Student Awards Luncheon.

yAISES members who attended the conference posing with the award onstage at the 2023 Student Awards Luncheon. (photo courtesy of yAISES)

One of more than 400 chapters around the country, yAISES won the Stelvio J. Zanin Distinguished Chapter of the Year Award for overall achievement in the promotion of the principles and goals of AISES. The national, nonprofit organization promotes the increased representation of Indigenous peoples of North America and the Pacific Islands in science, technology, engineering, and math (STEM) and STEM-adjacent studies and careers.

“As a chapter that got off the ground just two years ago, it’s amazing to see the impact, intellect, and community power that our members have inspired in such a short time,” said Madeline Gupta ’25, co-chair and co-founder of yAISES, which was revived in the spring semester of 2022 and is affiliated with Yale’s Native American Cultural Center. “I look forward to continuing a long partnership between Yale and Indigenous excellence in STEM fields.”

The Yale chapter is open to any Indigenous student in STEM or STEM-adjacent majors. Members meet regularly to pursue STEM and career building opportunities within and beyond Yale and raise awareness for Native political or cultural concerns related to STEM.

Put a ring on it

The most distant lensing galaxy ever discovered comes with some cosmic bling — known as an “Einstein ring.”

An Einstein ring forms when two galaxies align with Earth in a perfectly straight line, causing refracted starlight from the background galaxy to spill out in a circle around the foreground galaxy. It is a form of gravitational lensing, a phenomenon predicted by Albert Einstein’s theory of relativity.

In a new Nature Astronomy study led by Yale astronomer Pieter van Dokkum, researchers present details of an Einstein ring spotted by the James Webb Space Telescope (JWST). In this instance, sunlight from the background galaxy traveled 10.3 billion light years to reach Earth, making it the most distant lensing galaxy yet discovered.

“It’s quite an arresting image, and also the first Einstein ring that JWST has discovered,” said van Dokkum, the Sol Goldman Family Professor of Astronomy and professor of physics in Yale’s Faculty of Arts and Sciences.

The ring — now dubbed JWST-ER1 — also provides the researchers with important data about the enclosed mass of all material within the radius of the ring, which the researchers said is a “textbook” example of a massive galaxy that has stopped, or nearly stopped, producing new stars.

Co-authors of the study were Gabriel Brammer of the University of Copenhagen, Bingjie Wang and Joel Leja from Pennsylvania State University, and Charlie Conroy from the Harvard-Smithsonian Center for Astrophysics.

Demers, Xia elected American Physical Society fellows

A pair of Yale faculty members are among the 2023 class of American Physical Society (APS) fellows.

Sarah Demers, professor of physics in the Yale Faculty of Arts and Sciences, and Fengnian Xia, professor of electrical engineering at the Yale School of Engineering & Applied Science, were announced as new APS fellows last month. They are among 153 new fellows elected this year. Since 1921, 60 fellows have been elected from Yale.

No more than one-half of one percent of APS’s 50,000-plus members are elected fellows each year. Nominated candidates must be individuals who have advanced the field through significant achievements in original research, teaching, or the application of physics to science and technology.

Demers was honored for “important contributions to tau lepton triggering and identification and using the tau signature in the study of Higgs production and decay, and for important leadership both within the ATLAS collaboration and the broader physics community.”

 

Xia was honored for “foundational contributions to the study of optical properties of two-dimensional materials and their applications to optoelectronics and nanophotonics and contributions to the developments of silicon photonic integrated circuits.”

It’s a microscopic patch kit

All of life’s functions are orchestrated by communication between the cytoplasm of each cell and the cell’s nucleus, which houses chromosomes containing DNA, the genetic instruction manual of all organisms.

The success of this fundamental communication depends on the precise flow of information traffic between cytoplasm and the nucleus through regulated pores on the nuclear membrane that envelopes DNA. If the nuclear membrane is leaky, genetic information can become corrupted and molecules from the cytoplasm can leak into the nuclear compartment, destroying the cell’s ability to function properly.

Using an electron microscope, a Yale team headed by Nick Ader, postdoctoral fellow in the cell biology lab of Patrick Lusk and Megan King (the LusKing Lab) at Yale School of Medicine, discovered a new class of long-lived holes in the nuclear membrane that also need to be plugged. Instead of these nuclear holes being rapidly sealed by a machinery called the ESCRTs as expected, they instead are plugged by a second set of proteins that are part of what is known as the spindle pole body complex. While ESCRT proteins do keep these holes from getting too large, the spindle pole body complex in the meantime creates a temporary patch that prevents cytoplasm from flooding the nucleus, the researchers found.

Eventually, the nuclear membrane creates a more permanent seal with the help of the ESCRTs. “It’s like putting a plug into your car tire until you can buy a new one,” King said. Lusk and King suggest that malfunctions of this process may play a role in neurodegenerative diseases such ALS. The paper was published in the journal Nature Cell Biology.

Taking our best Energy Earthshot

The U.S. Department of Energy (DOE) recently announced funding for a series of Energy Earthshot Research Centers (EERCs) to accelerate breakthroughs to address difficult technological challenges necessary to limit the impacts of global warming.

One of those centers, called Terraforming Soil, will be based at Lawrence Livermore National Laboratory in California and include Yale scientists Eric Slessarev and Noah Planavsky among its principal investigators. Slessarev is an assistant professor of ecology and evolutionary biology in the Faculty of Arts and Sciences (FAS) and Planavsky is a professor of Earth and planetary sciences in FAS; both are members of the scientific leadership team of the Yale Center for Natural Carbon Capture.

Terraforming Soil will look at reversing the trend that has seen vast amounts of stored carbon dioxide leave America’s 166 million hectares of agricultural soil due to cultivation and erosion.

“One major goal of the EERC is to improve the mathematical models we use to simulate carbon cycling in soil,” Slessarev said. “I will be helping collaborators at Lawrence Livermore adapt and improve a model called Ecosys so that we can use it to better understand interactions between plants, mineral weathering, and organic carbon buildup in soil. I will also be helping to develop high-resolution maps of soil chemical properties that we can use to identify optimal locations for climate-friendly agricultural practices and soil-based carbon dioxide removal technologies.”

Planavsky will focus on quantifying carbon dioxide removal via enhanced silicate weathering at specific research sites.

Another Yale research team, which is exploring new frontiers in carbon capture technology, also received funding from the DOE’s Energy Earthshot initiative.

Research Redux:

Distinct immune, hormone responses shed light on mysteries of long COVID
At Yale, an effort to split water with record efficiency
Researchers find clues in obesity’s impact on breast cancer
The dazzling — and fortunate — story of gold
Yale scientists awaken the force in our cells
Fish, reconsidered: An updated ‘Tree of Life’ draws surprising connections